MCP1612 Single 1A, 1.4 MHz Synchronous Buck Regulator Features Description • Fixed Switching Frequency: 1.4MHz The MCP1612 is a 1A, 1.4MHz, fully-integrated, • Input Operating Voltage Range: 2.7V to 5.5V current mode-controlled, synchronous buck regulator. The MCP1612 is packaged in the 8-pin MSOP and • Integrated Buck and Synchronous Switches space-saving, 3x3 DFN packages. The DFN package • Adjustable-Output Voltage Range: 0.8V to 5.0V also provides a lower thermal resistance package • 100% Duty Cycle Capable for Low Input Voltage option for high-power, high ambient temperature • Continuous Output Current Capability: 1A applications. With an input operating range from 2.7V • Shutdown Control with IQ < 0.01µA (Typ.) to 5.5V, the MCP1612 is ideal for applications that are • Integrated Soft-Start Feature powered by one single-cell Li-Ion, 2- to 3-cell NiMH, NiCd or alkaline sources. • Integrated Undervoltage Lockout (UVLO) Protection The output voltage of the MCP1612 is easily set over • Integrated Overtemperature Protection the range of 0.8V to 5.0V by using an external resistor divider. The external inductor and output capacitor size • Fast Dynamic Response to Line and Load Steps are minimized due to an internally-fixed, 1.4MHz clock • Small, 8-Pin DFN and MSOP Packages being used to set the switching frequency. The fixed • Operating Temperature Range: -40°C to +85°C clock allows for continuous, fixed-frequency PWM operation over the full load range. Applications The MCP1612 is designed to provide fast dynamic • Network Interface Cards response to sudden changes in input voltage and load • Portable Computers current to minimize the necessary amount of external • Set-Top Boxes output capacitance. • DSL Modems and Routers The MCP1612 can be used with ceramic, tantalum or • USB-Powered Devices aluminum electrolytic output capacitors. Ceramic • GBIC Modules capacitors with values as low as 4.7µF can be used to • High-Speed Data System Bus Termination keep the output ripple voltage low. For applications that require better load step performance, the value of the • Medical Instruments output capacitor can be increased to 47µF. • Cellular/GSM/PHS Phones Additional features integrated into the MCP1612 • +5V or +3.3V Distributed Voltages include shutdown capability, soft-start, UVLO, overcurrent and overtemperature protection. Package Types 8-Lead DFN 8-Lead MSOP VIN 1 8 LX VIN 1 8 LX VCC 2 7 PGND VCC 2 7 PGND SHDN 3 6 A SHDN 3 6 A GND GND COMP 4 5 FB COMP 4 5 FB  2004-2013 Microchip Technology Inc. DS21921C-page 1

MCP1612 Functional Block Diagram VCC UndLeorcvkooltuatge UVLO VIN (UVLO) Slope Comp. ISENSE P-Channel + + Peak Current Limit PDRV Comp Disable VREF INSET LX Circuit NDRV FB – IN gm + Soft- Disable Start Disable V REF Peak Current 1.4MHz Clock Limit Leading- PGND Edge Blank P GND V CC V CC UVLO 1.2V Disable SHDN V BG A A GND Thermal Shutdown 0.8V A GND A GND DS21921C-page 2  2004-2013 Microchip Technology Inc.

MCP1612 Typical Application Circuit MCP1612 3.3V to 1.2V Synchronous Buck Converter L = 3.3µH 1.2V V @ 1A 8 OUT 3.3 VIN ±10% 1 V Lx IN C MCP1612 OUT CIN 10 10µF 100k Ceramic 10µF 2 7 V P Ceramic CC GND C BYP 0.1µF 6 Ceramic 3 SHDN AGND ON 200k OFF 5 4 FB Comp 25k 1000pF  2004-2013 Microchip Technology Inc. DS21921C-page 3

MCP1612 1.0 ELECTRICAL † Notice: Stresses above those listed under “Maximum Ratings” may cause permanent damage to the device. This is CHARACTERISTICS a stress rating only and functional operation of the device at those or any other conditions above those indicated in the Absolute Maximum Ratings † operational listings of this specification is not implied. Exposure to maximum rating conditions for extended periods VIN – AGND.......................................................................6.0V may affect device reliability. (SHDN, FB, V , Comp...........(A – 0.3V) to (V + 0.3V) CC GND IN L to P ..............................................-0.3V to (V + 0.3V) X GND IN P to A ...................................................-0.3V to +0.3V GND GND Output Short Circuit Current .................................Continuous Storage temperature.....................................-65°C to +150°C Ambient Temp. with Power Applied.................-40°C to +85°C Operating Junction Temperature...................-40°C to +125°C ESD protection on all pins (HBM)4kV ESD protection on all pins (MM)300V DC CHARACTERISTICS Electrical Specifications: Unless otherwise noted, V = V = V = 3.3V, V = 1.8V, C = C = 10µF, L = 3.3µH, IN CC SHDN OUT IN OUT I =100mA, T = +25°C. Boldface specifications apply over the T range of -40°C to +85°C. LOAD A A Parameters Sym Min Typ Max Units Conditions Input Voltage Input Operating Voltage V 2.7 — 5.5 V IN Input Shutdown Current I(V ) — 0.01 1 µA Shutdown mode (SHDN = GND) IN Input Quiescent Current I(V ) — 5 7 mA I = 0mA IN LOAD Oscillator Characteristics Internal Oscillator Frequency F 1.2 1.4 1.6 MHz OSC Internal Power Swicthes R P-Channel R — 300 — m I = 250mA DSon DSon-P P R N-Channel R — 300 — m I = 250mA DSon DSon-N N L Pin Leakage Current I -1 — 1 µA SHDN = 0V, V = 5.5V, L = 0V, X LX IN X L = 5.5V X Positive Current Limit Threshold +I — 2.3 — A LX(MAX) Negative Current Limit Threshold -I — -1.4 — A LX(MAX) Feedback Characteristics Transconductance from FB to g 35 62 90 µA/V m COMP Output Voltage Output Voltage Range V 0.8 — V V OUT IN Reference Feedback Voltage V 0.78 0.8 0.82 V FB Feedback Input Bias Current I — 1 — nA VFB Line Regulation V — 0.15 0.5 %/V V = 2.7V to 5.5V, I = 100mA LINE-REG IN LOAD Load Regulation V — 0.25 — % V = 4.2V, I = 100mA to 1A LOAD-REG IN LOAD Note 1: The integrated MOSFET switches have an integral diode from the L pin to V and from L to P . In cases where X IN X GND these diodes are forward-biased, the package power dissipation limits must be adhered to. Thermal protection is not able to regulate the junction temperature for these cases. 2: UVLO is specified for a falling V . Once the UVLO is activated, the UVLO- must be overcome before the device will IN HYS return to operation. DS21921C-page 4  2004-2013 Microchip Technology Inc.

MCP1612 DC CHARACTERISTICS (CONTINUED) Electrical Specifications: Unless otherwise noted, V = V = V = 3.3V, V = 1.8V, C = C = 10µF, L = 3.3µH, IN CC SHDN OUT IN OUT I =100mA, T = +25°C. Boldface specifications apply over the T range of -40°C to +85°C. LOAD A A Parameters Sym Min Typ Max Units Conditions Protection Features Undervoltage Lockout UVLO 2.4 2.55 2.7 V Note2 Undervoltage Lockout Hysteresis UVLO- — 200 — mV HYS Thermal Shutdown T — 160 — °C Note1 SHD Thermal Shutdown Hysteresis T — 9 — °C SHD-HYS Interface Signal (SHDN) Logic-High Input V 45 — — % of V IN-HIGH IN Logic-Low Input V — — 15 % of V IN-LOW IN Note 1: The integrated MOSFET switches have an integral diode from the L pin to V and from L to P . In cases where X IN X GND these diodes are forward-biased, the package power dissipation limits must be adhered to. Thermal protection is not able to regulate the junction temperature for these cases. 2: UVLO is specified for a falling V . Once the UVLO is activated, the UVLO- must be overcome before the device will IN HYS return to operation. TEMPERATURE SPECIFICATIONS Electrical Specifications: V = 3.0V to 5.5V, F = 1MHz with 10% Duty Cycle, C = 0.1µF. T =-40°C to +125°C. IN OSC IN A Parameters Sym Min Typ Max Units Conditions Temperature Ranges Storage Temperature Range T -65 — +150 °C Continuous A Maximum Junction Temperature T — — +150 °C Transient Only J Operating Junction Temperature Range T - 40 — + 125 °C Continuous Operation A Thermal Package Resistances Thermal Resistance, 8L-MSOP  — 208 — °C/W Typical 4-layer board interconnecting JA vias  — 41 — °C/W Typical 4-layer board interconnecting Thermal Resistance, 8L-DFN JA vias  2004-2013 Microchip Technology Inc. DS21921C-page 5

MCP1612 2.0 TYPICAL PERFORMANCE CURVES Note: The graphs and tables provided following this note are a statistical summary based on a limited number of samples and are provided for informational purposes only. The performance characteristics listed herein are not tested or guaranteed. In some graphs or tables, the data presented may be outside the specified operating range (e.g., outside specified power supply range) and therefore outside the warranted range. Note: Unless otherwise indicated, V = V = V = 3.3V, C = C = 10µF, L = 3.3µH, I = 100mA, IN CC SHDN OUT IN LOAD T =+25°C. Boldface specifications apply over the T range of -40°C to +85°C. A A 100 0.50 90 VOUT = 2.5V VOUT = 2.7V 80 V) 0.40 %) 70 VOUT = 1.2V ge ( ciency ( 456000 VOUT = 1.8V ut Volta 00..2300 VOUT = 3.3V Effi 30 opo 20 Dr 0.10 10 VIN = 3.3V 0 0.00 10 100 1000 0 200 400 600 800 1000 Load Current (mA) Load Current (mA) FIGURE 2-1: Efficiency vs. Load Current, FIGURE 2-4: Dropout Voltage vs. V = 3.3V. Load Current. IN 100 A) 6.5 90 m 80 VOUT = 3.3V nt ( 6.0 ncy (%)567000 VOUT = 2.5V nt Curre 55..05 TA = +85oC e e Effici3400 uiesc 4.5 TA = +25oC 12000 VIN = 5.0V Input Q 34..50 TA = -40oC VOUT = 1.8V 10 100 1000 2.5 3 3.5 4 4.5 5 5.5 Load Current (mA) Input Voltage (V) FIGURE 2-2: Efficiency vs. Load Current, FIGURE 2-5: Input Quiescent Current vs. V = 5.0V. Input Voltage. IN e (mV) -0.02 VOUT = 1.2V VIN = 3.3V MHz) 11..4412 TA = -40oC put Voltag --00..64 VOUT = 1.8V, VIN = 3.3V equency ( 11..3490 TA = +25oC ut -0.8 Fr Change In O --11-..142 VOUT = 3.3V, VIN = 5.0V Oscillator 111...333678 TA = +85oC 0 200 400 600 800 1000 2.5 3 3.5 4 4.5 5 5.5 Load Current (mA) Input Voltage (V) FIGURE 2-3: Output Voltage vs. FIGURE 2-6: Oscillator Frequency vs. Load Current. Input Voltage. DS21921C-page 6  2004-2013 Microchip Technology Inc.

MCP1612 TYPICAL PERFORMANCE CURVES (Continued) Note: Unless otherwise indicated, V = V = V = 3.3V, C = C = 10µF, L = 3.3µH, I = 100mA, IN CC SHDN OUT IN LOAD T =+25°C. Boldface specifications apply over the T range of -40°C to +85°C. A A Start-up from VIN = 0V to 3.3V IOUT = 100mA to 800mA V = 5.0V IN V = 3.3V V OUT OUT V 100mV/DIV IN 2.0V/DIV I OUT V 500mA/DIV OUT 1.0V/DIV VOUT = 1.8V 1.0ms/DIV 500µs/DIV FIGURE 2-7: Power-Up from V . FIGURE 2-10: Load Transient Response. IN Start-up from SHDN Line Step Response, VIN = 3.0V to 4.0V V IN SHDN 2.0V/DIV 2.0V/DIV V OUT 50mV/DIV V V = 1.8V OUT OUT 1.0V/DIV VOUT = 1.8V IOUT = 800mA 1.0ms/DIV 200µs/DIV FIGURE 2-8: Power-Up from Shutdown. FIGURE 2-11: Line Transient Response. I = 100mA to 800mA Line Step Response, V = 4.5V to 5.5V OUT IN V IN V 2.0V/DIV OUT 200mV/DIV V OUT 50mV/DIV I OUT 500mA/DIV V = 3.3V OUT VOUT = 1.8V IOUT = 800mA 50µs/DIV 200µs/DIV FIGURE 2-9: Load Transient Response. FIGURE 2-12: Line Transient Response.  2004-2013 Microchip Technology Inc. DS21921C-page 7

MCP1612 TYPICAL PERFORMANCE CURVES (Continued) Note: Unless otherwise indicated, V = V = V = 3.3V, C = C = 10µF, L = 3.3µH, I = 100mA, IN CC SHDN OUT IN LOAD T = +25°C. Boldface specifications apply over the T range of -40°C to +85°C. A A I = 10mA, V = 1.8V I = 1A, V = 1.8V OUT OUT OUT OUT L X L X 5.0V/DIV 2.0V/DIV V V OUT OUT 10mV/DIV 10mV/DIV I IND I IND 500mA/DIV 100mA/DIV V = 3.3V V = 3.3V IN IN 500ns/DIV 500ns/DIV FIGURE 2-13: Low Load Current Switching FIGURE 2-14: High Load Current Switching Waveform. Waveform. DS21921C-page 8  2004-2013 Microchip Technology Inc.

MCP1612 3.0 MCP1612 PIN DESCRIPTIONS The descriptions of the pins are listed in Table3-1. TABLE 3-1: PIN FUNCTION TABLE Pin No. Name Function 1 V Input Voltage Pin IN 2 V Analog Input Voltage Pin CC 3 SHDN Shutdown Control Input Pin 4 COMP Transconductance Amplifier Output Pin 5 FB Feedback Input Pin 6 A Analog Ground Pin GND 7 P Power Ground Pin GND 8 L Buck Inductor Output Pin X 3.1 Input Voltage Pin (V ) 3.5 Feedback Pin (FB) IN Connect the input voltage source to V . For normal Connect the output voltage of the buck converter IN operation, the voltage on V should be between +2.7V through an external resistor divider to FB to regulate IN and +5.5V. A 10µF bypass capacitor should be the output voltage. The nominal voltage compared to connected between V and P . this input for pulse termination is 0.8V. IN GND 3.2 Analog Input Voltage Pin (V ) 3.6 Analog Ground Pin (A ) CC GND V provides bias for internal analog functions. This Tie all small-signal ground returns to A . Noise on CC GND voltage is derived by filtering the V supply. A can effect the sensitive internal analog IN GND measurements. 3.3 Shutdown Input Pin (SHDN) 3.7 Power Ground Pin (P ) GND Connect SHDN to a logic-level input in order to turn the regulator on or off. A logic-high (>45% of V ) will Connect all large-signal ground returns to P . These IN GND enable the regulator. A logic-low (<15% of V ) will large-signal traces should have a small loop area and IN force the regulator into Shutdown mode. When in length to prevent coupling of switching noise to shutdown, both the P-channel and N-channel switches sensitive traces. are turned off. 3.8 Buck Inductor Output Pin (L ) X 3.4 Compensation Pin (COMP) Connect L directly to the buck inductor. This pin X COMP is the internal transconductance amplifier carries large signal-level currents; all connections output pin. External compensation is connected to should be made as short as possible. COMP for control-loop stabilization.  2004-2013 Microchip Technology Inc. DS21921C-page 9

MCP1612 4.0 DETAILED DESCRIPTION 4.4 Current Limit Cycle-by-cycle current limit is used to protect the 4.1 Device Overview MCP1612 from being damaged when an external short The MCP1612 is a 1A synchronous buck converter circuit is applied. The typical peak current limit is 2.3A. switching at 1.4MHz to minimize external component If the sensed inductor current reaches the 2.3A limit, size and cost. While utilizing a fixed-frequency Current the P-channel MOSFET is turned off, even if the output mode architecture, the MCP1612 provides fast voltage is not in regulation. response to sudden load changes, as well as 4.5 Soft-Start overcurrent protection in the event of a shorted load. The input voltage range is 2.7V to 5.5V, while the During normal power-up, as V rises above the UVLO output voltage is adjustable by properly setting an IN protection setting (or, in the case of a logic-low to logic- external resistor divider and can range from 0.8V to high transition on the shutdown pin), the rise time of the V . Integrated soft-start, UVLO and overtemperature IN MCP1612 output voltage is controlled by the soft-start protection minimize external circuitry and component feature. This is accomplished by allowing the output of count. the error amplifier to slowly rise. This feature prevents the output voltage from overshooting the desired value 4.2 Current Mode Control Scheme and the sudden inrush of current, depleting the input The MCP1612 incorporates a Peak Current mode capacitors and causing a large dip in input voltage. This control scheme. Peak Current mode is used to obtain large dip in the input voltage can trip the UVLO thresh- high gain in the PWM control loop for very fast old, causing the converter to shut down prior to reach- response to dynamic line and load conditions. With ing steady-state operation. both the P-channel and N-channel MOSFETs turned off, the beginning of a cycle occurs on the negative 4.6 Undervoltage Lockout (UVLO) edge of the internal 1.4MHz oscillator, the P-channel MOSFET turns on and current ramps up into the buck The UVLO feature uses a comparator to sense the input voltage level (V ). If the input voltage is lower inductor. The inductor current is sensed and tied to one IN than the voltage necessary to properly operate the input of a high-speed comparator. The other input of MCP1612, the UVLO feature will hold the converter off. the high-speed comparator is the error amplifier output. When V rises above the necessary input voltage, the This is the amplified difference between the internal IN UVLO is released and soft-start begins. For the 0.8V reference and the divided-down V signal at OUT the FB pin of the MCP1612. When the sensed inductor MCP1612, the UVLO protection threshold is at a current ramps up to the point that is equal to the maximum of 2.7V. Hysteresis is built into the UVLO amplified error signal, the high-speed comparator circuit to compensate for input impedance. For output switches states and the P-channel MOSFET is example, if there is any resistance between the input voltage source and the converter (once it starts), there turned off until the beginning of the next clock cycle and the N-channel is turned on. The width of the pulse (or will be a voltage drop at the converter input equal to duty cycle) is ideally determined by the VOUT/VIN ratio IINx RIN. The typical hysteresis for the MCP1612 is of the DC/DC converter. The actual duty cycle is slightly 200mV. larger to account for the non-ideal losses of the integrated MOSFET switches and the losses in the 4.7 Overtemperature Protection external inductor. The MCP1612 has an integrated overtemperature 4.3 Low-Dropout Operation protection circuit that monitors the device junction temperature and shuts the device off if the junction The MCP1612 is capable of operating over a wide temperature exceeds the typical 160°C threshold. If the range of input voltages. The PWM architecture allows overtemperature threshold is reached, the soft-start is for the P-channel MOSFET to achieve 100% duty cycle reset so that, when the junction temperature cools to operation for applications that have minimal input volt- approximately 151°C, the device will automatically age headroom. During 100% Duty Cycle mode, the restart and the output voltage will not overshoot. output voltage (V ) is equal to the Output Current OUT (IOUT) x Resistance (P-channel RDSON + RINDUCTOR). 4.8 Shutdown Input Operation The SHDN pin is used to turn the MCP1612 on and off. When the SHDN pin is tied low, the MCP1612 is off. When tied high, the MCP1612 will be enabled and begin operation as long as the input voltage is not below the UVLO threshold. DS21921C-page 10  2004-2013 Microchip Technology Inc.

MCP1612 5.0 APPLICATION CIRCUITS/INFORMATION MCP1612 3.3V to 1.2V Synchronous Buck Converter L = 3.3µH 1.2V V @ 1A 8 OUT 3.3VIN ±10% 1 V Lx IN C MCP1612 OUT CIN 10 10µF 100k Ceramic 10µF 2 7 V P Ceramic CC GND C BYP 0.1µF 6 Ceramic 3 SHDN AGND ON 200k OFF 5 4 FB Comp 25k 1000pF FIGURE 5-1: Typical Application Circuit. 5.1 Typical Applications resistors will make the circuit more susceptible to noise on the FB pin. Lower-value resistors can be used, if The MCP1612 buck controller can be used in several necessary. different applications where a voltage that is lower than Equation5-1, used to calculate the output voltage, is the supply voltage is required. Its small size, low cost shown below. and high efficiency make the MCP1612 a good choice for densely-packaged applications. The input voltage EQUATION 5-1: range, low-dropout voltage and low shutdown current make this part perfectly suited for battery-powered V applications. R1 = R2--V--O----U----T-–1 FB Where: 5.2 Design Example V = desired output voltage The step-by-step design of a buck converter with the OUT following parameters is presented to illustrate how VFB = MCP1612 internal reference easy the MCP1612 is to use. voltage R = top resistor value Input voltage =3.3V 1 R = bottom resistor value Output voltage =1.2V 2 Output current =0A to 1A For this example: Switching frequency =1.4MHz V = 1.2V OUT 5.2.1 SETTING OUTPUT VOLTAGE VFB = 0.8V R = 200k The output voltage of the MCP1612 is set by using an 2 external resistor-divider network. The voltage present R = 100k 1 at FB is internally compared to a 0.8V reference The MCP1612 is capable of a 15% duty cycle. voltage. A 200kresistor is recommended for R , the 2 Instability may result when the duty cycle is below 15%. lower-end of the voltage divider. Using higher-value If less than 15% duty cycle operation is needed, care must be taken to ensure stable operation.  2004-2013 Microchip Technology Inc. DS21921C-page 11

MCP1612 5.2.2 BUCK INDUCTOR The value of the buck inductor is chosen to be 3.3µH. The AC ripple current is controlled by the size of the There are many requirements that need to be satisfied buck inductor. The value of the inductor will therefore when selecting the buck inductor. The application, need to be raised so that the converter operates in physical size, current rating, resistance, mounting Continuous Conduction mode. Calculation of the buck method, supplier, temperature range, minimum inductor current rating follows. inductance and cost all need to be considered. V = 3.3V Many suppliers specify the maximum peak current that IN an inductor can handle before magnetic saturation V = 1.2V OUT occurs. The peak current is equal to the maximum DC F = 1.4MHz SW output current, plus one-half the peak-to-peak AC I = 1A ripple current. OUT(MAX) T = (1.2V/3.3V) x (1/1.4MHz) When the P-channel MOSFET is on, the current in the ON T = 260ns buck inductor is ramped up. The voltage across the ON inductor, the inductance and the MOSFET on-time are V = (3.3V – 1.2V) = 2.1V L required to determine the peak-to-peak ripple current. I = (2.1V/3.3µH) x 260ns L When operating in Continuous Current mode, the on- I = 165mA L time of the P-channel MOSFET is determined by I = I + 1/2 I multiplying the duty cycle by the switching period. The L(PEAK) OUT(MAX) L I = 1A + (165mA)/2 following equation can be used to determine the duty L(PEAK) cycle. I = 1.08A L(PEAK) The inductor selected must have an inductance of EQUATION 5-2: 3.3µH at a peak current rating of 1.08A. The DC resis- V tance of the inductor should be as low as is feasibly DutyCycle = ----O----U----T- possible. Extremely low DC resistance inductors are V IN available, though a trade-off between size and cost should be considered. The on-time is then defined as follows. 5.2.3 OUTPUT CAPACITOR EQUATION 5-3: The output capacitor is used to filter the inductor AC 1 ripple current and provide storage for load transients. T = DutyCycle---------- ON F The size and Equivalent Series Resistance (ESR) of SW the output capacitor determines the amount of ripple Where: voltage present at the output of the converter. When FSW = switching frequency selecting the output capacitor, a design trade-off has to be made between the acceptable ripple voltage and the The AC ripple current in the inductor can be calculated size/cost of the output capacitor. Ceramic capacitors by the following relationship. have very low ESR, but increase in cost with higher values. Tantalum and electrolytic capacitors are EQUATION 5-4: relatively inexpensive in higher values, but they also have a much higher ESR. I L V = L-------- The amount of capacitance needed to obtain the L t desired ripple voltage is calculated by using the following relationship. Solving for I yields: L EQUATION 5-6: EQUATION 5-5: V V I = C--------C--- I = ----L--t C t L L Where: V = voltage across the inductor L (V – V ) IN OUT t = on-time of the P-channel MOSFET DS21921C-page 12  2004-2013 Microchip Technology Inc.

MCP1612 Solving for C: 5.2.6 COMPENSATION COMPONENTS t An internal transconductance error amplifier is used to C = I ----------- C V compensate the buck converter. An external resistor C (R ) and capacitor (C ), connected between COMP Where: C C and GND, are all that is needed to provide a high- I = peak-to-peak ripple current bandwidth loop. C t = on-time of P-channel MOSFET Table5-1 identifies values for R and C for standard C C VC = output ripple voltage buck inductor (L) and output capacitor (COUT) values. TABLE 5-1: R and C VALUES There will also be some ripple voltage caused by the C C ESR of the capacitor. The ripple is defined as follows. L C R C OUT C C 3.3µH 10.0µF 25k 1000pF EQUATION 5-7: 2.2µH 4.7µF 10k 1000pF V = ESRI ESRRIPPLE C 5.3 Printed Circuit Board (PCB) For this example: Layout I = 165mA The MCP1612 is capable of switching over 1A at C C = 4.7µF 1.4MHz. As with all high-frequency switching power supplies, good PCB layout techniques are essential to t = 260ns prevent noise generated by the switching power-train ESR = 8m from interfering with the sensing circuitry. VC = (260ns x 165mA)/4.7µF There are two ground pins (PGND and AGND) on the V = 9.13mV MCP1612 to separate the large-signal ground current C V = 8m x 165mA from the small-signal circuit ground. These two ESRRIPPLE grounds should be kept separate, only connecting near V = 1.32mV ESRRIPPLE the input bulk capacitor. V = V + V OUT C ESRRIPPLE Care must also be taken to minimize the length and VOUT = 9.13mV + 1.32mV loop area of the large signal connections. Components V = 10.45mV connected to this loop consist of the input bulk OUT capacitor, V , P and L pins of the MCP1612, the IN GND X 5.2.4 INPUT CAPACITOR buck inductor and the output filter capacitor. For the buck topology, the input current is pulled from the source and the input capacitor in pulses. The size of the input capacitor will determine the amount of current pulled from the source. For most applications, a 10µF ceramic capacitor connected between the MCP1612’s V and P is recommended to filter the IN GND current pulses. Less capacitance can be used for applications that have low source impedance. The ripple current rating for ceramic capacitors are typically very high due to their low loss characteristics. Low-cost electrolytic capacitors can be used, but their ripple current rating should not be exceeded. 5.2.5 V INPUT CC The V input is used to bias the internal MCP1612 CC circuitry. A 10 resistor is recommended between the unregulated inputs V and V , along with a 0.1µF IN CC capacitor to ground to help isolate the V pin from the CC switching noise.  2004-2013 Microchip Technology Inc. DS21921C-page 13

MCP1612 6.0 PACKAGING INFORMATION 6.1 Package Marking Information 8-Lead DFN (3mm x 3mm) Example: XXXX 1612 YYWW I0532 NNN 256 8-Lead MSOP Example: XXXXX 1612I YWWNNN 532256 Legend: XX...X Customer-specific information Y Year code (last digit of calendar year) YY Year code (last 2 digits of calendar year) WW Week code (week of January 1 is week ‘01’) NNN Alphanumeric traceability code e3 Pb-free JEDEC designator for Matte Tin (Sn) * This package is Pb-free. The Pb-free JEDEC designator ( e 3 ) can be found on the outer packaging for this package. Note: In the event the full Microchip part number cannot be marked on one line, it will be carried over to the next line, thus limiting the number of available characters for customer-specific information. DS21921C-page 14  2004-2013 Microchip Technology Inc.

MCP1612 8-Lead Plastic Dual-Flat, No-Lead Package (MF) 3x3x0.9 mm Body (DFN) – Saw Singulated Note: For the most current package drawings, please see the Microchip Packaging Specification located at http://www.microchip.com/packaging D p b n L EXPOSED METAL PAD E E2 (NOTE 2) PIN 1 2 1 ID INDEX D2 AREA TOP VIEW BOTTOM VIEW (NOTE 1) ALTERNATE EXPOSED PAD CONFIGURATIONS A1 A EXPOSED A3 TIE BAR (NOTE 3) Units INCHES MILLIMETERS* Dimension Limits MIN NOM MAX MIN NOM MAX Number of Pins n 8 8 Pitch p .026 BSC 0.65 BSC Overall Height A .031 .035 .039 0.80 0.90 1.00 Standoff A1 .000 .001 .002 0.00 0.02 0.05 Contact Thickness A3 .008 REF. 0.20 REF. Overall Length E .118 BSC 3.00 BSC Exposed Pad Width E2 .043 .061 .063 1.09 1.55 1.60 Overall Width D .118 BSC 3.00 BSC Exposed Pad Length D2 .059 .092 .096 1.50 2.37 2.45 Contact Width b .009 .012 .015 0.23 0.30 0.37 Contact Length L .008 .016 .020 0.20 0.40 0.50 * Controlling Parameter Notes: 1. Pin 1 visual index feature may vary, but must be located within the hatched area. 2. Exposed pad varies according to die attach paddle size. 3. Package may have one or more exposed tie bars at ends. BSC: Basic Dimension. Theoretically exact value shown without tolerances. See ASME Y14.5M REF: Reference Dimension, usually without tolerance, for information purposes only. See ASME Y14.5M JEDEC equivalent: M0-229 Revised 07-20-05 Drawing No. C04-062  2004-2013 Microchip Technology Inc. DS21921C-page 15

MCP1612 8-Lead Plastic Micro Small Outline Package (MS) (MSOP) Note: For the most current package drawings, please see the Microchip Packaging Specification located at http://www.microchip.com/packaging E E1 p D 2 B n 1  c  A A2 F L A1  Units INCHES MILLIMETERS* Dimension Limits MIN NOM MAX MIN NOM MAX Number of Pins n 8 8 Pitch p .026 BSC 0.65 BSC Overall Height A - - .043 - - 1.10 Molded Package Thickness A2 .030 .033 .037 0.75 0.85 0.95 Standoff A1 .000 - .006 0.00 - 0.15 Overall Width E .193 BSC 4.90 BSC Molded Package Width E1 .118 BSC 3.00 BSC Overall Length D .118 BSC 3.00 BSC Foot Length L .016 .024 .031 0.40 0.60 0.80 Footprint (Reference) F .037 REF 0.95 REF Foot Angle  0° - 8° 0° - 8° Lead Thickness c .003 .006 .009 0.08 - 0.23 Lead Width B .009 .012 .016 0.22 - 0.40 Mold Draft Angle Top  5° - 15° 5° - 15° Mold Draft Angle Bottom  5° - 15° 5° - 15° * Controlling Parameter Notes: Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed .010" (0.254mm) per side. BSC: Basic Dimension. Theoretically exact value shown without tolerances. See ASME Y14.5M REF: Reference Dimension, usually without tolerance, for information purposes only. See ASME Y14.5M JEDEC Equivalent: MO-187 Revised 07-21-05 Drawing No. C04-111 DS21921C-page 16  2004-2013 Microchip Technology Inc.

MCP1612 APPENDIX A: REVISION HISTORY Revision C (January 2013) Added a note to each package outline drawing. Revision B (September 2005) The following is the list of modifications: 1. Changed pin 6 in Package Types diagram on front page. 2. Removed device qualification note in Package Marking section. 3. Removed device qualification note in Package Outline drawing. 4. Removed device qualification note in Package Identification System section 5. Replaced MSOP and QFN package diagrams. Revision A (December 2004) • Original Release of this Document.  2004-2013 Microchip Technology Inc. DS21921C-page 17

MCP1612 NOTES: DS21921C-page 18  2004-2013 Microchip Technology Inc.

MCP1612 PRODUCT IDENTIFICATION SYSTEM To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office. PART NO. X /XX Examples: a) MCP1612-ADJI/MS: Industrial Temperature, Device Temperature Package 8LD MSOP package. Range b) MCP1612T-ADJI/MS: Tape and Reel Industrial Temperature, 8LD MSOP package. Device: MCP1612: Synchronous Buck Regulator c) MCP1612-ADJI/MF: Industrial Temperature, MCP1612T: Synchronous Buck Regulator 8LD DFN package. (Tape and Reel) d) MCP1612T-ADJI/MF: Tape and Reel Industrial Temperature, 8LD DFN package. Temperature Range: I = -40°C to +85°C Package: MF = Dual Flat, No Lead (3x3mm Body), 8-lead MS = Plastic MSOP, 8-lead  2004-2013 Microchip Technology Inc. DS21921C-page 19

MCP1612 NOTES: DS21921C-page 20  2004-2013 Microchip Technology Inc.

Note the following details of the code protection feature on Microchip devices: • Microchip products meet the specification contained in their particular Microchip Data Sheet. • Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the intended manner and under normal conditions. • There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data Sheets. Most likely, the person doing so is engaged in theft of intellectual property. • Microchip is willing to work with the customer who is concerned about the integrity of their code. • Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not mean that we are guaranteeing the product as “unbreakable.” Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our products. Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act. Information contained in this publication regarding device Trademarks applications and the like is provided only for your convenience The Microchip name and logo, the Microchip logo, dsPIC, and may be superseded by updates. It is your responsibility to FlashFlex, KEELOQ, KEELOQ logo, MPLAB, PIC, PICmicro, ensure that your application meets with your specifications. PICSTART, PIC32 logo, rfPIC, SST, SST Logo, SuperFlash MICROCHIP MAKES NO REPRESENTATIONS OR and UNI/O are registered trademarks of Microchip Technology WARRANTIES OF ANY KIND WHETHER EXPRESS OR Incorporated in the U.S.A. and other countries. IMPLIED, WRITTEN OR ORAL, STATUTORY OR OTHERWISE, RELATED TO THE INFORMATION, FilterLab, Hampshire, HI-TECH C, Linear Active Thermistor, INCLUDING BUT NOT LIMITED TO ITS CONDITION, MTP, SEEVAL and The Embedded Control Solutions QUALITY, PERFORMANCE, MERCHANTABILITY OR Company are registered trademarks of Microchip Technology FITNESS FOR PURPOSE. Microchip disclaims all liability Incorporated in the U.S.A. arising from this information and its use. Use of Microchip Silicon Storage Technology is a registered trademark of devices in life support and/or safety applications is entirely at Microchip Technology Inc. in other countries. the buyer’s risk, and the buyer agrees to defend, indemnify and Analog-for-the-Digital Age, Application Maestro, BodyCom, hold harmless Microchip from any and all damages, claims, chipKIT, chipKIT logo, CodeGuard, dsPICDEM, suits, or expenses resulting from such use. No licenses are dsPICDEM.net, dsPICworks, dsSPEAK, ECAN, conveyed, implicitly or otherwise, under any Microchip ECONOMONITOR, FanSense, HI-TIDE, In-Circuit Serial intellectual property rights. Programming, ICSP, Mindi, MiWi, MPASM, MPF, MPLAB Certified logo, MPLIB, MPLINK, mTouch, Omniscient Code Generation, PICC, PICC-18, PICDEM, PICDEM.net, PICkit, PICtail, REAL ICE, rfLAB, Select Mode, SQI, Serial Quad I/O, Total Endurance, TSHARC, UniWinDriver, WiperLock, ZENA and Z-Scale are trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. SQTP is a service mark of Microchip Technology Incorporated in the U.S.A. GestIC and ULPP are registered trademarks of Microchip Technology Germany II GmbH & Co. & KG, a subsidiary of Microchip Technology Inc., in other countries. All other trademarks mentioned herein are property of their respective companies. © 2004-2013, Microchip Technology Incorporated, Printed in the U.S.A., All Rights Reserved. Printed on recycled paper. ISBN: 9781620769164 QUALITY MANAGEMENT SYSTEM Microchip received ISO/TS-16949:2009 certification for its worldwide headquarters, design and wafer fabrication facilities in Chandler and CERTIFIED BY DNV Tempe, Arizona; Gresham, Oregon and design centers in California and India. The Company’s quality system processes and procedures == ISO/TS 16949 == are for its PIC® MCUs and dsPIC® DSCs, KEELOQ® code hopping devices, Serial EEPROMs, microperipherals, nonvolatile memory and analog products. In addition, Microchip’s quality system for the design and manufacture of development systems is ISO 9001:2000 certified.  2004-2013 Microchip Technology Inc. DS21921C-page 21

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